Predictive testing to identify a mutation in the HD gene in asymptomatic people has been available since 1993. Persons completing testing are at risk for decreased functional health prior to the onset of symptoms of this disease. However, little is known regarding the impact of this knowledge on family members. Understanding of the impact of HD on family members is en important issue for the future implementation of presymptomatic genetic testing of healthy persons. Gene mutations are being identified for other adult-onset, familial, degenerative neurologic disorders. Experience with HD can serve as a model for implementing predictive testing. The purpose of this study is to identify health management concerns and needs of family members of asymptomatic and symptomatic persons with a mutation in the gene for HD. There are 2 specific aims for this study. Specific Aim 1 is to examine the impact of HD on a family member's 1) own emotional and functional health status, 2) perceptions of health problems in the proband, 3) resources/strategies for managing these problems, 4) perceptions of what has and has not been helpful, and 5) perceptions of what services are needed to help family members cope. This will be accomplished in two phases. Phase 1 consists of conducting focus groups with persons who are related to, or identify themselves as family to persons with a HD gene mutation. Focus groups of 6-S people will be piloted in Iowa, and convened in 5 additional sites. Data from the focus groups will be analyzed through content analysis to identify salient themes and key issues. In Phase 2, a survey instrument will be developed and field tested. Specific Aim 2 is to describe the health care needs, management strategies, and needs for health and social services of relatives/significant others in families in which a person has a gene mutation for HD. In Phase 3, the survey will be distributed to family members of all persons who enroll in the PREDICT-HD study and persons from these sites with HD who are symptomatic. These individuals will be recruited from the participants enrolled in the 20-site Neurobiological Predictors of HD (PREDICT-HD) ROI NS40068 study whose purpose is to determine the progressive changes in caudate and putamen volume, basal ganglia dopamine D2 receptors, and determine progressive cognitive and behavioral changes in persons with CAG expansions in the HD gene. Frequencies and comparisons of survey responses according to respondent characteristics will be reported. This study will document the health care needs of family members of persons who receive a positive result from presymptomatic gene testing for an inherited degenerative neurologic disease.